Engine cooling system for vehicle

ABSTRACT

An engine cooling system for a vehicle may include a cooling unit that circulates coolant through a cooling line connecting a water jacket, a water pump, and a radiator of an engine to cool the engine, and a sub-cooling unit that selectively circulates coolant through a sub-cooling line connecting the engine with a refrigerator so as to cool the engine.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2012-0065143 filed on Jun. 18, 2012, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention related to an engine cooling system for a vehicle. More particularly, the present invention relates to an engine cooling system for a vehicle that supplies an engine with cooled coolant to cool an overheated combustion chamber according to a driving condition of an engine.

2. Description of Related Art

Generally, a part of the heat that is generated from combustion chambers of an engine is absorbed by a cylinder head, a cylinder block, an intake/exhaust valve, and a piston.

These components can be transformed by the excessive heat of the combustion chamber or an oil film of the cylinder can be damaged thereby.

Accordingly, the excessive heat causes combustion fault, knocking, or pre-ignition to damage the piston and the cylinder block, and the heat efficiency and the output can be deteriorated. In contrast, excessive cooling of the engine can deteriorate output, increases fuel consumption, and causes low temperature abrasion of the cylinder.

Accordingly, a cooling system is disposed to cool the engine in a vehicle and the coolant is circulated to the engine through a cooling line, the engine cooling system operates a water pump to cool the coolant through a radiator, and the coolant passes a cylinder block, a cylinder head, and a heater of an engine.

Here, a water jacket is formed in the cylinder block and the coolant is circulated through the water jacket such that the coolant cools the area of a spark plug corresponding to the combustion chamber or the area of an exhaust port and a valve seat.

However, a conventional engine cooling system circulates coolant that is cooled by the radiator, and therefore it can be hard to efficiently cool the engine.

Also, the temperature of the overall engine is increased by the overheated combustion chamber in a high speed/high load driving condition of the engine, the power output can be deteriorated, the fuel consumption can be increased, and the overall durability of the engine can be deteriorated.

The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing an engine cooling system for a vehicle having advantages of having a separate cooling line as well as a main cooling line such that main cooled coolant is circulated and supplied to an engine according to the driving condition of the engine such that the overheated circumference of a combustion chamber is effectively cooled and the cooling performance of the engine is improved in a high speed/high load driving condition.

In an aspect of the present invention, an engine cooling system for a vehicle, may include a cooling unit that circulates coolant through a cooling line connecting a water jacket, a water pump, and a radiator of an engine to cool the engine, and a sub-cooling unit that selectively circulates coolant through a sub-cooling line connecting the engine with a refrigerator so as to cool the engine.

The refrigerator is disposed outside the engine, wherein the sub-cooling line may include a first line that is diverged from the cooling line that connects the water pump with the engine and connected to the refrigerator to supply the refrigerator with coolant, and a second line connecting the refrigerator and a sub-water jacket of the engine to supply the sub-water jacket with the coolant passing through the refrigerator.

A valve is mounted in the second line between the refrigerator and the sub-water jacket.

The valve opens the sub-cooling line to supply the sub-water jacket with the coolant that is cooled by the refrigerator when the engine is in a speed condition or a load condition.

The sub-water jacket may include a first connection passage that is formed at both lateral sides in a length direction of a cylinder head and connected to the second line of the sub-cooling line, and at least a second connection passage that is connected to the first connection passage and is respectively formed corresponding to a combustion chamber.

One end side of the second connection passage is connected to the first connection passage and the other end side thereof is formed toward an inner side of the cylinder head, and the second connection passage is formed vertically with regard to the first connection passage.

The sub-water jacket may include a first connection passage that is formed at both lateral sides in a length direction of a cylinder head and connected to the second line of the sub-cooling line, and at least a second connection passage that is connected to the first connection passage and is respectively formed between combustion chambers.

One end side of the second connection passage is connected to the first connection passage and the other end side thereof is formed toward an inner side of the cylinder head, and the second connection passage is formed vertically with regard to the first connection passage.

As described above, an engine cooling system for a vehicle according to an exemplary embodiment of the present invention has a separate cooling line as well as a main cooling line such that the main coolant is circulated and supplies the cooled coolant to the engine according to the driving condition of the engine such that the overheated circumference of a combustion chamber is effectively cooled and the cooling performance thereof is improved in a high speed/high load driving condition.

Also, the engine is effectively cooled according to the driving condition thereof to prevent overheating, to improve the durability thereof, and to improve knocking characteristics such that power performance and fuel efficiency of the vehicle are improved and the overall product quality is also improved.

The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an engine cooling system for a vehicle according to an exemplary embodiment of the present invention.

FIG. 2 is a side view of a cylinder head that is applied to an engine cooling system for a vehicle according to an exemplary embodiment of the present invention.

FIG. 3 is a cross-sectional view taken along the A-A line of FIG. 2.

FIG. 4 is a perspective view of a water jacket that is applied in a cylinder head in an engine cooling system for a vehicle according to an exemplary embodiment of the present invention.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.

An exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of an engine cooling system for a vehicle according to an exemplary embodiment of the present invention, FIG. 2 is a side view of a cylinder head that is applied to an engine cooling system for a vehicle according to an exemplary embodiment of the present invention, FIG. 3 is a cross-sectional view taken along the A-A line of FIG. 2, and FIG. 4 is a perspective view of a water jacket that is applied in a cylinder head in an engine cooling system for a vehicle according to an exemplary embodiment of the present invention.

Referring to the drawings, an engine cooling system 100 for a vehicle according to an exemplary embodiment of the present invention includes a main cooling line 120 through which main coolant circulates and a separate cooling line, and supplies an engine 110 with cooled coolant according to the operating conditions of the engine 110 such that the area of the heated combustion chamber is effectively cooled to improve cooling performance in the high speed/high load driving condition.

For this, in the engine cooling system 100 for a vehicle according to an exemplary embodiment of the present invention, as shown in FIG. 1, the engine 110 is connected to a radiator 140 through the cooling line 120.

Also, the coolant that is cooled by the radiator 140 is supplied to a water jacket 115 of the engine 110 including a cylinder head 113 and a cylinder block 111 through the operation of a water pump 130 that is disposed between the radiator 140 and the engine 110 in the cooling line 120.

Here, the water jacket 115 is formed in the engine 110 and the coolant is supplied to the water jacket 115 through the cooling line 120.

A sub-cooling unit 150 includes a refrigerator 151, a sub-cooling line 153, and a sub-water jacket 155 in the present exemplary embodiment.

The sub-cooling line 153 includes a first line that is connected to the cooling line 120 and a second line that is connected to the sub-water jacket 155 of the engine 110.

Firstly, the refrigerator 151 is disposed inside a non-illustrated engine compartment outside of the engine 100. The refrigerator 151 includes a separate heat exchanger or an evaporator of an air-conditioning system.

In the present exemplary embodiment, the sub-cooling line 153 diverges from the cooling line 120 that connects the water pump 130 and the engine 110, supplies the refrigerator with the coolant, and is connected to the engine 110 to supply the sub-water jacket 155 of the engine 110 with the coolant that is cooled by the refrigerator 151.

That is, the refrigerator 151 cools the coolant, wherein the coolant is cooled by another cooling liquid flowing through the refrigerator 151 such as a refrigerant.

Here, a valve 157 is disposed between the engine 110 and the refrigerator 151 in the second line of the sub-cooling line 153.

The valve 157 opens the sub-cooling line 153 to supply the sub-water jacket 155 with the coolant that is cooled when the engine 110 is operated in a high speed/high load condition.

That is, the valve 157 is connected to an ECU of a non-illustrated vehicle, selectively opens the sub-cooling line 153 that is connected to the engine 110 according to the driving condition of the engine, and selectively supplies the engine with the coolant that is cooled by the refrigerator 151.

Further, the sub-water jacket 155 is formed in the cylinder head 113 of the engine 110 and is connected to the sub-cooling line 153 to supply the inside of the engine 110 with the cooled coolant.

Here, as shown in FIG. 2 and FIG. 3, the sub-water jacket 155 includes a first connection passage 155 a that is formed at both sides of the cylinder head 113 in a length direction, and at least one second connection passage 155 b that is connected to the first connection passage 155 a and is formed corresponding to a combustion chamber 200 of the engine 110.

In an exemplary embodiment of the present invention, at least one second connection passage 155 b may be formed between combustion chambers 200 of the engine 110.

One end of the second connection passage 155 b is connected to the first connection passage 155 a and the other end thereof is formed toward the inside of the cylinder head 113 to be disposed in a vertical direction with regard to the first connection passage 155 a in the present exemplary embodiment.

The second connection passage 155 b is formed at a lower side of an interval of an intake port and an exhaust port corresponding to each combustion chamber of the engine 110 such that the cooled coolant flows through the second connection passage 155 b.

For the sub-water jacket 155 that is described above, as shown in FIG. 4, when the engine is operated in a high speed/high load condition, if the valve 157 is operated to open the sub-cooling line 152, the coolant flows through the first connection passage 155 a that is formed at lower both sides of the cylinder head 113 of the engine 110.

Further, the coolant that is supplied to the first connection passage 155 a is supplied to the second connection passage 155 b that is formed at a lower side of an interval of an intake port and an exhaust port of the water jacket 115 to effectively cool the combustion chamber of the engine 110 such that overheating of the engine 110 is prevented.

That is, the sub-cooling unit 150 closes the valve in a low speed/low load condition of the engine 110 such that the coolant is not supplied to the engine, and on the contrary, the sub-cooling unit 150 opens the valve in a high speed/high load condition of the engine 110 such that the coolant is supplied to the sub-water jacket of the engine to cool the circumference of the combustion chamber.

Accordingly, an engine cooling system 100 according to an exemplary embodiment of the present invention additionally supplies the coolant that is cooled depending on the driving condition of the engine 110 to control the temperature of the intake and exhaust ports and the combustion chamber such that the overheating of the engine is prevented.

Therefore, if the vehicle engine cooling system 100 as describe above is applied to an exemplary embodiment of the present invention, the sub-cooling unit 150 as well as the cooling line 120 are disposed to circulate coolant.

Further, the coolant that is cooled depending on the driving condition of the engine 110 is supplied to the engine 110, so the overheating of the combustion chamber is effectively reduced in a high speed/high load driving condition to improve the cooling performance thereof.

Also, the engine 110 is effectively cooled according to the driving condition of the engine and overheating of the engine is prevented such that the durability, the fuel efficiency, the power performance, and the overall product quality of the vehicle are improved.

For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. 

What is claimed is:
 1. An engine cooling system for a vehicle, comprising: a cooling unit that circulates coolant through a cooling line connecting a water jacket, a water pump, and a radiator of an engine to cool the engine; and a sub-cooling unit that selectively circulates coolant through a sub-cooling line connecting the engine with a refrigerator so as to cool the engine.
 2. The engine cooling system for the vehicle of claim 1, wherein the refrigerator is disposed outside the engine, and wherein the sub-cooling line includes: a first line that is diverged from the cooling line that connects the water pump with the engine and connected to the refrigerator to supply the refrigerator with coolant; and a second line connecting the refrigerator and a sub-water jacket of the engine to supply the sub-water jacket with the coolant passing through the refrigerator.
 3. The engine cooling system for the vehicle of claim 2, wherein a valve is mounted in the second line between the refrigerator and the sub-water jacket.
 4. The engine cooling system for the vehicle of claim 3, wherein the valve opens the sub-cooling line to supply the sub-water jacket with the coolant that is cooled by the refrigerator when the engine is in a speed condition or a load condition.
 5. The engine cooling system for the vehicle of claim 2, wherein the sub-water jacket includes: a first connection passage that is formed at both lateral sides in a length direction of a cylinder head and connected to the second line of the sub-cooling line; and at least a second connection passage that is connected to the first connection passage and is respectively formed corresponding to a combustion chamber.
 6. The engine cooling system for the vehicle of claim 5, wherein one end side of the second connection passage is connected to the first connection passage and the other end side thereof is formed toward an inner side of the cylinder head, and the second connection passage is formed vertically with regard to the first connection passage.
 7. The engine cooling system for the vehicle of claim 2, wherein the sub-water jacket includes: a first connection passage that is formed at both lateral sides in a length direction of a cylinder head and connected to the second line of the sub-cooling line; and at least a second connection passage that is connected to the first connection passage and is respectively formed between combustion chambers.
 8. The engine cooling system for the vehicle of claim 7, wherein one end side of the second connection passage is connected to the first connection passage and the other end side thereof is formed toward an inner side of the cylinder head, and the second connection passage is formed vertically with regard to the first connection passage. 